Objective
To examine back muscle activity and fatigue behavior in female patients with degenerative thoracolumbar kyphosis (DTK) using high-density surface electromyography (HDSEMG) and evaluate the effects of using a soft spinal orthosis.
Methods
Seven female participants with DTK (mean age: 73.6 years) were assessed during static standing and a weighted holding task with and without a soft spinal orthosis. HDSEMG signals were obtained from the lumbar erector spinae using a 64-electrode array. Time to fatigue (TTF), spatial displacement, and directional consistency of muscle activation were analyzed using the spatial center of activity (SCoA) and circular variance (CV).
Results
Orthosis use significantly reduced the sagittal vertical axis and low back pain. TTF was significantly prolonged during the weighted holding task with the orthosis (p=0.012), indicating delayed fatigue onset. SCoA displacement was significantly reduced in both tasks (p<0.001), whereas CV analysis demonstrated improved directional consistency of muscle activation.
Conclusion
HD-SEMG revealed early fatigue onset and unstable muscle activation patterns in patients with DTK, particularly during load-bearing tasks performed without orthotic support. Orthosis used improved endurance and neuromuscular efficiency by reducing spatial and directional variability in muscle recruitment. These findings underscore the utility of HDSEMG for elucidating the neuromuscular pathophysiology of DTK and support the use of spinal orthoses as a conservative treatment approach.

Objective
To investigate the effects of social restrictions imposed during the coronavirus disease 2019 (COVID-19) pandemic on postoperative functional recovery in patients who underwent surgery for degenerative musculoskeletal disorders.
Methods
This longitudinal prospective cohort study included 291 patients categorized into pre-pandemic (surgery in 2018), early pandemic (2019), and late-pandemic (2020) groups based on their 1-year recovery period. The primary outcome was improvement in locomotive syndrome (LS) status 1 year after surgery. We analyzed the association between social limitations and LS improvement using multivariate logistic and segmented regression analyses.
Results
The late-pandemic group exhibited the lowest LS improvement rate (50.6%) and the highest prevalence of postoperative social contact limitations (61.0%). Multivariate analysis identified the absence of postoperative social contact limitation as a highly potent independent predictor of LS improvement (odds ratio, 10.01; 95% confidence interval, 5.40–19.34; p<0.01). Segmented regression analysis revealed a time lag: social contact limitations peaked in March 2020, whereas the decline in LS improvement rates began in October 2020.
Conclusion
Prolonged social restrictions negatively impacted functional recovery, particularly during the late phase of the pandemic. Social participation, specifically direct social contact, could be a critical and independent component of postoperative rehabilitation. These findings underscore the need to integrate psychosocial assessments into standard postoperative care to optimize patient outcomes.

Objective
To examine the efficacy and safety of an innovative, device-driven abdominal trunk muscle strengthening program, with the ability to measure muscle strength, to treat chronic low back pain (LBP) in elderly participants.
Methods
Seven women with non-specific chronic LBP, lasting at least 3 months, were enrolled and treated with the prescribed exercise regimen. Patients participated in a 12-week device-driven exercise program which included abdominal trunk muscle strengthening and 4 types of stretches for the trunk and lower extremities. Primary outcomes were adverse events associated with the exercise program, improvement in abdominal trunk muscle strength, as measured by the device, and improvement in the numerical rating scale (NRS) scores of LBP with the exercise. Secondary outcomes were improvement in the Roland-Morris Disability Questionnaire (RDQ) score and the results of the locomotive syndrome risk test, including the stand-up and two-step tests.
Results
There were no reports of increased back pain or new-onset abdominal pain or discomfort during or after the device-driven exercise program. The mean abdominal trunk muscle strength, NRS, RDQ scores, and the stand-up and two-step test scores were significantly improved at the end of the trial compared to baseline.
Conclusion
No participants experienced adverse events during the 12-week strengthening program, which involved the use of our device and stretching, indicating the program was safe. Further, the program significantly improved various measures of LBP and physical function in elderly participants.

Citations

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  Satoshi Nagatani, Satoru Demura, Satoshi Kato, Tamon Kabata, Yoshitomo Kajino, Noriaki Yokogawa, Daisuke Inoue, Yuki Kurokawa, Motoya Kobayashi, Yohei Yamada, Masafumi Kawai, Hiroyuki Tsuchiya
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